Isolated calcification of tricuspid valve with severe low pressure tricuspid regurgitation in an infant

Abstract

A three-month-old asymptomatic male infant was evaluated for a systolic murmur. Echocardiography revealed calcification of tricuspid leaflets with severe low pressure tricuspid regurgitation. Pulmonary artery flow was normal. There was no other congenital anomaly.

1. Case report

A three-month-old asymptomatic male infant was referred for evaluation of a systolic murmur. He was first child born of full term normal delivery. He did not have any systemic illness or any congenital defect and was not receiving any drug. Peripheral arterial pulsations were normal and arteries were not thickened. There was no history of perinatal hypoxia, perineal infection or stormy neonatal course. Skiagram of chest was normal. Mother denied any history of illness, radiation exposure or drugs during pregnancy. She was not suffering from diabetes or any other chronic illness.

'Echocardiography revealed dilatation of right atrium and right ventricle with calcification of tricuspid leaflets (Fig. 1A). Tricuspid leaflets were normally attached. There was no appreciable subvalvular pathology. Right ventricular endomyocardium showed normal echo texture without any evidence of fibrosis, calcification, non-compaction or thrombus formation. Ventricular apices were normal. Interatrial septum was intact (Fig. 1B). Interventricular septum showed diastolic flattening in short axis view (Fig. 1C). Color Doppler evaluation showed severe tricuspid regurgitation (Fig. 2A). Continuous wave Doppler evaluation of tricuspid regurgitation jet revealed right ventricular systolic pressure of 17.3 mm Hg (Fig. 2B). Diastolic flow across tricuspid valve was normal with no evidence of stenosis (Fig. 2C). Pulmonary valve was normal. On pulsed Doppler evaluation, pulmonary artery flow was normal with peak velocity of 1.08 m.s. (peak gradient 4.5 mm Hg) and acceleration time of 111 min (Fig. 2D). Superior vena cava, inferior vena cava and hepatic veins were normal in size and flow pattern was normal (Fig. 3A–C). Mitral valve was normal with normal flow pattern (Fig. 3D). Left ventricle, aorta and coronary sinus were normal. Parents did not agree for treatment and further evaluation as the infant was asymptomatic. Parents did not bring the infant for follow up.

Fig. 1.

A – Apical 4 chamber view showing calcification of tricuspid leaflets (TV) with dilated right atrium (RA) and right ventricle (RV). B – Subcostal view with focus on atria showing intact interatrial septum. RA – right atrium, LA – Left atrium. C – Magnified short axis view showing diastolic flattening of interventricular septum (IVS). ES – end systolic, ED – end diastolic, RV – right ventricle, LV – left ventricle.

Fig. 2.

A – Color Doppler evaluation in modified apical five chamber view showing severe tricuspid regurgitation. RV – right ventricle, RA – right atrium, AO – Aorta. B – Continuous wave Doppler evaluation of tricuspid regurgitation jet. C – Pulsed wave Doppler evaluation of tricuspid flow. E – Early diastolic flow, A – Late diastolic flow. D – Pulsed Doppler evaluation of pulmonary artery flow.

Fig. 3.

A – Pulsed Doppler evaluation of superior vena cava flow from subcostal view. EXP – expiration, INSP – Inspiration. B – M-mode evaluation of inferior vena cava. IVC – inferior vena cava, RA – right atrium, Exp – expiration, INSP – Inspiration. C – Pulsed Doppler evaluation of hepatic vein flow. D – Pulsed Doppler evaluation of mitral flow. E – early diastolic flow, A – late diastolic flow.

2. Discussion

Trivial tricuspid regurgitation is common in normal neonates.¹ Such tricuspid regurgitation is localized to a small area (<1 cm) near the valve closure. Jet is thin, central, does not extend throughout systole and is of low velocity (≤2.5 m/s).¹ Severe, low pressure tricuspid regurgitation in an infant can be due to Ebstein anomaly of tricuspid valve, endomyocardial fibrosis, dilated right ventricular cardiomyopathy or tricuspid valve dysplasia. Our patient did not have any echocardiographic finding suggestive of these diseases. Severe tricuspid regurgitation may occur in newborns due to premature closure of PDA. Such TR decreases over time as the pulmonary vascular resistance decreases. Our infant was three-month-old and there was no echocardiographic evidence of pulmonary artery hypertension. Perinatal hypoxia and perineal infections can cause nonspecific myocardial injury and secondary calcification. Our patient did not have any such history. Valvular and annular calcification could be due to degenerative process and could be associated with idiopathic arterial calcification. Our case did not have such features. Cause of calcium deposits in tricuspid leaflets in our patient is not clear. We could not find any similar report in literature.² Our case could be a variant of dysplastic tricuspid valve presenting with dominant tricuspid regurgitation without any element of stenosis or right ventricular hypoplasia. Genetic mutation has been found to be associated with late onset calcific stenosis of aortic valve.³ Some yet unidentified genetic mutation could be responsible for isolated tricuspid calcification in infancy as seen in our patient.

Conflicts of interest

The author has none to declare.